1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2006 Vadim Goncharov <vadimnuclight@tpu.ru> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice unmodified, this list of conditions, and the following 12 * disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * Portions Copyright (c) 1999 Whistle Communications, Inc. 30 * (ng_bpf by Archie Cobbs <archie@freebsd.org>) 31 */ 32 33 /* 34 * TAG NETGRAPH NODE TYPE 35 * 36 * This node type accepts an arbitrary number of hooks. Each hook can be 37 * configured for an mbuf_tags(9) definition and two hook names: a hook 38 * for matched packets, and a hook for packets, that didn't match. Incoming 39 * packets are examined for configured tag, matched packets are delivered 40 * out via first hook, and not matched out via second. If corresponding hook 41 * is not configured, packets are dropped. 42 * 43 * A hook can also have an outgoing tag definition configured, so that 44 * all packets leaving the hook will be unconditionally appended with newly 45 * allocated tag. 46 * 47 * Both hooks can be set to null tag definitions (that is, with zeroed 48 * fields), so that packet tags are unmodified on output or all packets 49 * are unconditionally forwarded to non-matching hook on input. There is 50 * also a possibility to replace tags by specifying strip flag on input 51 * and replacing tag on corresponding output tag (or simply remove tag if 52 * no tag specified on output). 53 * 54 * If compiled with NG_TAG_DEBUG, each hook also keeps statistics about 55 * how many packets have matched, etc. 56 */ 57 58 #include <sys/param.h> 59 #include <sys/systm.h> 60 #include <sys/errno.h> 61 #include <sys/kernel.h> 62 #include <sys/malloc.h> 63 #include <sys/mbuf.h> 64 #include <sys/stddef.h> 65 66 #include <netgraph/ng_message.h> 67 #include <netgraph/netgraph.h> 68 #include <netgraph/ng_parse.h> 69 #include <netgraph/ng_tag.h> 70 71 #ifdef NG_SEPARATE_MALLOC 72 static MALLOC_DEFINE(M_NETGRAPH_TAG, "netgraph_tag", "netgraph tag node"); 73 #else 74 #define M_NETGRAPH_TAG M_NETGRAPH 75 #endif 76 77 #define ERROUT(x) do { error = (x); goto done; } while (0) 78 79 /* 80 * Per hook private info. 81 * 82 * We've separated API and ABI here, to make easier changes in this node, 83 * if needed. If you want to change representation, please do not break API. 84 * We still keep API structures in memory to simplify access to them for 85 * GET* messages, but most of data is accessed in internal representation 86 * only. The reason for this is to speed things up - if data will be 87 * accessed from API structures, there would be double pointer dereferencing 88 * in the code, which almost necessarily leads to CPU cache misses and 89 * reloads. 90 * 91 * We also do another optimization by using resolved pointers to 92 * destination hooks instead of expensive ng_findhook(). 93 */ 94 struct ng_tag_hookinfo { 95 hook_p hi_match; /* matching hook pointer */ 96 hook_p hi_nonmatch; /* non-matching hook pointer */ 97 uint32_t in_tag_cookie; 98 uint32_t out_tag_cookie; 99 uint16_t in_tag_id; 100 uint16_t in_tag_len; 101 uint16_t out_tag_id; 102 uint16_t out_tag_len; 103 uint8_t strip; 104 void *in_tag_data; 105 void *out_tag_data; 106 struct ng_tag_hookin *in; 107 struct ng_tag_hookout *out; 108 #ifdef NG_TAG_DEBUG 109 struct ng_tag_hookstat stats; 110 #endif 111 }; 112 typedef struct ng_tag_hookinfo *hinfo_p; 113 114 /* Netgraph methods. */ 115 static ng_constructor_t ng_tag_constructor; 116 static ng_rcvmsg_t ng_tag_rcvmsg; 117 static ng_shutdown_t ng_tag_shutdown; 118 static ng_newhook_t ng_tag_newhook; 119 static ng_rcvdata_t ng_tag_rcvdata; 120 static ng_disconnect_t ng_tag_disconnect; 121 122 /* Internal helper functions. */ 123 static int ng_tag_setdata_in(hook_p hook, const struct ng_tag_hookin *hp); 124 static int ng_tag_setdata_out(hook_p hook, const struct ng_tag_hookout *hp); 125 126 /* Parse types for the field 'tag_data' in structs ng_tag_hookin and out. */ 127 static int 128 ng_tag_hookinary_getLength(const struct ng_parse_type *type, 129 const u_char *start, const u_char *buf) 130 { 131 const struct ng_tag_hookin *hp; 132 133 hp = (const struct ng_tag_hookin *) 134 (buf - offsetof(struct ng_tag_hookin, tag_data)); 135 return (hp->tag_len); 136 } 137 138 static int 139 ng_tag_hookoutary_getLength(const struct ng_parse_type *type, 140 const u_char *start, const u_char *buf) 141 { 142 const struct ng_tag_hookout *hp; 143 144 hp = (const struct ng_tag_hookout *) 145 (buf - offsetof(struct ng_tag_hookout, tag_data)); 146 return (hp->tag_len); 147 } 148 149 static const struct ng_parse_type ng_tag_hookinary_type = { 150 &ng_parse_bytearray_type, 151 &ng_tag_hookinary_getLength 152 }; 153 154 static const struct ng_parse_type ng_tag_hookoutary_type = { 155 &ng_parse_bytearray_type, 156 &ng_tag_hookoutary_getLength 157 }; 158 159 /* Parse type for struct ng_tag_hookin. */ 160 static const struct ng_parse_struct_field ng_tag_hookin_type_fields[] 161 = NG_TAG_HOOKIN_TYPE_INFO(&ng_tag_hookinary_type); 162 static const struct ng_parse_type ng_tag_hookin_type = { 163 &ng_parse_struct_type, 164 &ng_tag_hookin_type_fields 165 }; 166 167 /* Parse type for struct ng_tag_hookout. */ 168 static const struct ng_parse_struct_field ng_tag_hookout_type_fields[] 169 = NG_TAG_HOOKOUT_TYPE_INFO(&ng_tag_hookoutary_type); 170 static const struct ng_parse_type ng_tag_hookout_type = { 171 &ng_parse_struct_type, 172 &ng_tag_hookout_type_fields 173 }; 174 175 #ifdef NG_TAG_DEBUG 176 /* Parse type for struct ng_tag_hookstat. */ 177 static const struct ng_parse_struct_field ng_tag_hookstat_type_fields[] 178 = NG_TAG_HOOKSTAT_TYPE_INFO; 179 static const struct ng_parse_type ng_tag_hookstat_type = { 180 &ng_parse_struct_type, 181 &ng_tag_hookstat_type_fields 182 }; 183 #endif 184 185 /* List of commands and how to convert arguments to/from ASCII. */ 186 static const struct ng_cmdlist ng_tag_cmdlist[] = { 187 { 188 NGM_TAG_COOKIE, 189 NGM_TAG_SET_HOOKIN, 190 "sethookin", 191 &ng_tag_hookin_type, 192 NULL 193 }, 194 { 195 NGM_TAG_COOKIE, 196 NGM_TAG_GET_HOOKIN, 197 "gethookin", 198 &ng_parse_hookbuf_type, 199 &ng_tag_hookin_type 200 }, 201 { 202 NGM_TAG_COOKIE, 203 NGM_TAG_SET_HOOKOUT, 204 "sethookout", 205 &ng_tag_hookout_type, 206 NULL 207 }, 208 { 209 NGM_TAG_COOKIE, 210 NGM_TAG_GET_HOOKOUT, 211 "gethookout", 212 &ng_parse_hookbuf_type, 213 &ng_tag_hookout_type 214 }, 215 #ifdef NG_TAG_DEBUG 216 { 217 NGM_TAG_COOKIE, 218 NGM_TAG_GET_STATS, 219 "getstats", 220 &ng_parse_hookbuf_type, 221 &ng_tag_hookstat_type 222 }, 223 { 224 NGM_TAG_COOKIE, 225 NGM_TAG_CLR_STATS, 226 "clrstats", 227 &ng_parse_hookbuf_type, 228 NULL 229 }, 230 { 231 NGM_TAG_COOKIE, 232 NGM_TAG_GETCLR_STATS, 233 "getclrstats", 234 &ng_parse_hookbuf_type, 235 &ng_tag_hookstat_type 236 }, 237 #endif 238 { 0 } 239 }; 240 241 /* Netgraph type descriptor. */ 242 static struct ng_type typestruct = { 243 .version = NG_ABI_VERSION, 244 .name = NG_TAG_NODE_TYPE, 245 .constructor = ng_tag_constructor, 246 .rcvmsg = ng_tag_rcvmsg, 247 .shutdown = ng_tag_shutdown, 248 .newhook = ng_tag_newhook, 249 .rcvdata = ng_tag_rcvdata, 250 .disconnect = ng_tag_disconnect, 251 .cmdlist = ng_tag_cmdlist, 252 }; 253 NETGRAPH_INIT(tag, &typestruct); 254 255 /* 256 * This are default API structures (initialized to zeroes) which are 257 * returned in response to GET* messages when no configuration was made. 258 * One could ask why to have this structures at all when we have 259 * ng_tag_hookinfo initialized to zero and don't need in and out structures 260 * at all to operate. Unfortunatelly, we have to return thisHook field 261 * in response to messages so the fastest and simpliest way is to have 262 * this default structures and initialize thisHook once at hook creation 263 * rather than to do it on every response. 264 */ 265 266 /* Default tag values for a hook that matches nothing. */ 267 static const struct ng_tag_hookin ng_tag_default_in = { 268 { '\0' }, /* to be filled in at hook creation time */ 269 { '\0' }, 270 { '\0' }, 271 0, 272 0, 273 0, 274 0 275 }; 276 277 /* Default tag values for a hook that adds nothing */ 278 static const struct ng_tag_hookout ng_tag_default_out = { 279 { '\0' }, /* to be filled in at hook creation time */ 280 0, 281 0, 282 0 283 }; 284 285 /* 286 * Node constructor. 287 * 288 * We don't keep any per-node private data - we do it on per-hook basis. 289 */ 290 static int 291 ng_tag_constructor(node_p node) 292 { 293 return (0); 294 } 295 296 /* 297 * Add a hook. 298 */ 299 static int 300 ng_tag_newhook(node_p node, hook_p hook, const char *name) 301 { 302 hinfo_p hip; 303 int error; 304 305 /* Create hook private structure. */ 306 hip = malloc(sizeof(*hip), M_NETGRAPH_TAG, M_NOWAIT | M_ZERO); 307 if (hip == NULL) 308 return (ENOMEM); 309 NG_HOOK_SET_PRIVATE(hook, hip); 310 311 /* 312 * After M_ZERO both in and out hook pointers are set to NULL, 313 * as well as all members and pointers to in and out API 314 * structures, so we need to set explicitly only thisHook field 315 * in that structures (after allocating them, of course). 316 */ 317 318 /* Attach the default IN data. */ 319 if ((error = ng_tag_setdata_in(hook, &ng_tag_default_in)) != 0) { 320 free(hip, M_NETGRAPH_TAG); 321 return (error); 322 } 323 324 /* Attach the default OUT data. */ 325 if ((error = ng_tag_setdata_out(hook, &ng_tag_default_out)) != 0) { 326 free(hip, M_NETGRAPH_TAG); 327 return (error); 328 } 329 330 /* 331 * Set hook name. This is done only once at hook creation time 332 * since hook name can't change, rather than to do it on every 333 * response to messages requesting API structures with data who 334 * we are etc. 335 */ 336 strncpy(hip->in->thisHook, name, sizeof(hip->in->thisHook) - 1); 337 hip->in->thisHook[sizeof(hip->in->thisHook) - 1] = '\0'; 338 strncpy(hip->out->thisHook, name, sizeof(hip->out->thisHook) - 1); 339 hip->out->thisHook[sizeof(hip->out->thisHook) - 1] = '\0'; 340 return (0); 341 } 342 343 /* 344 * Receive a control message. 345 */ 346 static int 347 ng_tag_rcvmsg(node_p node, item_p item, hook_p lasthook) 348 { 349 struct ng_mesg *msg; 350 struct ng_mesg *resp = NULL; 351 int error = 0; 352 353 NGI_GET_MSG(item, msg); 354 switch (msg->header.typecookie) { 355 case NGM_TAG_COOKIE: 356 switch (msg->header.cmd) { 357 case NGM_TAG_SET_HOOKIN: 358 { 359 struct ng_tag_hookin *const 360 hp = (struct ng_tag_hookin *)msg->data; 361 hook_p hook; 362 363 /* Sanity check. */ 364 if (msg->header.arglen < sizeof(*hp) || 365 msg->header.arglen < NG_TAG_HOOKIN_SIZE(hp->tag_len)) 366 ERROUT(EINVAL); 367 368 /* Find hook. */ 369 if ((hook = ng_findhook(node, hp->thisHook)) == NULL) 370 ERROUT(ENOENT); 371 372 /* Set new tag values. */ 373 if ((error = ng_tag_setdata_in(hook, hp)) != 0) 374 ERROUT(error); 375 break; 376 } 377 378 case NGM_TAG_SET_HOOKOUT: 379 { 380 struct ng_tag_hookout *const 381 hp = (struct ng_tag_hookout *)msg->data; 382 hook_p hook; 383 384 /* Sanity check. */ 385 if (msg->header.arglen < sizeof(*hp) || 386 msg->header.arglen < NG_TAG_HOOKOUT_SIZE(hp->tag_len)) 387 ERROUT(EINVAL); 388 389 /* Find hook. */ 390 if ((hook = ng_findhook(node, hp->thisHook)) == NULL) 391 ERROUT(ENOENT); 392 393 /* Set new tag values. */ 394 if ((error = ng_tag_setdata_out(hook, hp)) != 0) 395 ERROUT(error); 396 break; 397 } 398 399 case NGM_TAG_GET_HOOKIN: 400 { 401 struct ng_tag_hookin *hp; 402 hook_p hook; 403 404 /* Sanity check. */ 405 if (msg->header.arglen == 0) 406 ERROUT(EINVAL); 407 msg->data[msg->header.arglen - 1] = '\0'; 408 409 /* Find hook. */ 410 if ((hook = ng_findhook(node, msg->data)) == NULL) 411 ERROUT(ENOENT); 412 413 /* Build response. */ 414 hp = ((hinfo_p)NG_HOOK_PRIVATE(hook))->in; 415 NG_MKRESPONSE(resp, msg, 416 NG_TAG_HOOKIN_SIZE(hp->tag_len), M_WAITOK); 417 /* M_WAITOK can't return NULL. */ 418 bcopy(hp, resp->data, 419 NG_TAG_HOOKIN_SIZE(hp->tag_len)); 420 break; 421 } 422 423 case NGM_TAG_GET_HOOKOUT: 424 { 425 struct ng_tag_hookout *hp; 426 hook_p hook; 427 428 /* Sanity check. */ 429 if (msg->header.arglen == 0) 430 ERROUT(EINVAL); 431 msg->data[msg->header.arglen - 1] = '\0'; 432 433 /* Find hook. */ 434 if ((hook = ng_findhook(node, msg->data)) == NULL) 435 ERROUT(ENOENT); 436 437 /* Build response. */ 438 hp = ((hinfo_p)NG_HOOK_PRIVATE(hook))->out; 439 NG_MKRESPONSE(resp, msg, 440 NG_TAG_HOOKOUT_SIZE(hp->tag_len), M_WAITOK); 441 /* M_WAITOK can't return NULL. */ 442 bcopy(hp, resp->data, 443 NG_TAG_HOOKOUT_SIZE(hp->tag_len)); 444 break; 445 } 446 447 #ifdef NG_TAG_DEBUG 448 case NGM_TAG_GET_STATS: 449 case NGM_TAG_CLR_STATS: 450 case NGM_TAG_GETCLR_STATS: 451 { 452 struct ng_tag_hookstat *stats; 453 hook_p hook; 454 455 /* Sanity check. */ 456 if (msg->header.arglen == 0) 457 ERROUT(EINVAL); 458 msg->data[msg->header.arglen - 1] = '\0'; 459 460 /* Find hook. */ 461 if ((hook = ng_findhook(node, msg->data)) == NULL) 462 ERROUT(ENOENT); 463 stats = &((hinfo_p)NG_HOOK_PRIVATE(hook))->stats; 464 465 /* Build response (if desired). */ 466 if (msg->header.cmd != NGM_TAG_CLR_STATS) { 467 NG_MKRESPONSE(resp, 468 msg, sizeof(*stats), M_WAITOK); 469 /* M_WAITOK can't return NULL. */ 470 bcopy(stats, resp->data, sizeof(*stats)); 471 } 472 473 /* Clear stats (if desired). */ 474 if (msg->header.cmd != NGM_TAG_GET_STATS) 475 bzero(stats, sizeof(*stats)); 476 break; 477 } 478 #endif /* NG_TAG_DEBUG */ 479 480 default: 481 error = EINVAL; 482 break; 483 } 484 break; 485 default: 486 error = EINVAL; 487 break; 488 } 489 done: 490 NG_RESPOND_MSG(error, node, item, resp); 491 NG_FREE_MSG(msg); 492 return (error); 493 } 494 495 /* 496 * Receive data on a hook. 497 * 498 * Apply the filter, and then drop or forward packet as appropriate. 499 */ 500 static int 501 ng_tag_rcvdata(hook_p hook, item_p item) 502 { 503 struct mbuf *m; 504 struct m_tag *tag = NULL; 505 const hinfo_p hip = NG_HOOK_PRIVATE(hook); 506 uint16_t type, tag_len; 507 uint32_t cookie; 508 hinfo_p dhip; 509 hook_p dest; 510 #ifdef NG_TAG_DEBUG 511 int totlen; 512 #endif 513 int found = 0, error = 0; 514 515 m = NGI_M(item); /* 'item' still owns it.. we are peeking */ 516 #ifdef NG_TAG_DEBUG 517 totlen = m->m_pkthdr.len; 518 519 hip->stats.recvFrames++; 520 hip->stats.recvOctets += totlen; 521 #endif 522 523 /* Looking up incoming tag. */ 524 cookie = hip->in_tag_cookie; 525 type = hip->in_tag_id; 526 tag_len = hip->in_tag_len; 527 528 /* 529 * We treat case of all zeroes specially (that is, cookie and 530 * type are equal to zero), as we assume that such tag 531 * can never occur in the wild. So we don't waste time trying 532 * to find such tag (for example, these are zeroes after hook 533 * creation in default structures). 534 */ 535 if ((cookie != 0) || (type != 0)) { 536 tag = m_tag_locate(m, cookie, type, NULL); 537 while (tag != NULL) { 538 if (memcmp((void *)(tag + 1), 539 hip->in_tag_data, tag_len) == 0) { 540 found = 1; 541 break; 542 } 543 tag = m_tag_locate(m, cookie, type, tag); 544 } 545 } 546 547 /* See if we got a match and find destination hook. */ 548 if (found) { 549 #ifdef NG_TAG_DEBUG 550 hip->stats.recvMatchFrames++; 551 hip->stats.recvMatchOctets += totlen; 552 #endif 553 if (hip->strip) 554 m_tag_delete(m, tag); 555 dest = hip->hi_match; 556 } else 557 dest = hip->hi_nonmatch; 558 if (dest == NULL) { 559 NG_FREE_ITEM(item); 560 return (0); 561 } 562 563 /* Deliver frame out destination hook. */ 564 dhip = NG_HOOK_PRIVATE(dest); 565 566 #ifdef NG_TAG_DEBUG 567 dhip->stats.xmitOctets += totlen; 568 dhip->stats.xmitFrames++; 569 #endif 570 571 cookie = dhip->out_tag_cookie; 572 type = dhip->out_tag_id; 573 tag_len = dhip->out_tag_len; 574 575 if ((cookie != 0) || (type != 0)) { 576 tag = m_tag_alloc(cookie, type, tag_len, M_NOWAIT); 577 /* XXX may be free the mbuf if tag allocation failed? */ 578 if (tag != NULL) { 579 if (tag_len != 0) { 580 /* copy tag data to its place */ 581 memcpy((void *)(tag + 1), 582 dhip->out_tag_data, tag_len); 583 } 584 m_tag_prepend(m, tag); 585 } 586 } 587 588 NG_FWD_ITEM_HOOK(error, item, dest); 589 return (error); 590 } 591 592 /* 593 * Shutdown processing. 594 */ 595 static int 596 ng_tag_shutdown(node_p node) 597 { 598 NG_NODE_UNREF(node); 599 return (0); 600 } 601 602 /* 603 * Hook disconnection. 604 * 605 * We must check all hooks, since they may reference this one. 606 */ 607 static int 608 ng_tag_disconnect(hook_p hook) 609 { 610 const hinfo_p hip = NG_HOOK_PRIVATE(hook); 611 node_p node = NG_HOOK_NODE(hook); 612 hook_p hook2; 613 614 KASSERT(hip != NULL, ("%s: null info", __func__)); 615 616 LIST_FOREACH(hook2, &node->nd_hooks, hk_hooks) { 617 hinfo_p priv = NG_HOOK_PRIVATE(hook2); 618 619 if (priv->hi_match == hook) 620 priv->hi_match = NULL; 621 if (priv->hi_nonmatch == hook) 622 priv->hi_nonmatch = NULL; 623 } 624 625 free(hip->in, M_NETGRAPH_TAG); 626 free(hip->out, M_NETGRAPH_TAG); 627 free(hip, M_NETGRAPH_TAG); 628 NG_HOOK_SET_PRIVATE(hook, NULL); /* for good measure */ 629 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) && 630 (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) { 631 ng_rmnode_self(NG_HOOK_NODE(hook)); 632 } 633 return (0); 634 } 635 636 /************************************************************************ 637 HELPER STUFF 638 ************************************************************************/ 639 640 /* 641 * Set the IN tag values associated with a hook. 642 */ 643 static int 644 ng_tag_setdata_in(hook_p hook, const struct ng_tag_hookin *hp0) 645 { 646 const hinfo_p hip = NG_HOOK_PRIVATE(hook); 647 struct ng_tag_hookin *hp; 648 int size; 649 650 /* Make a copy of the tag values and data. */ 651 size = NG_TAG_HOOKIN_SIZE(hp0->tag_len); 652 hp = malloc(size, M_NETGRAPH_TAG, M_WAITOK); 653 /* M_WAITOK can't return NULL. */ 654 bcopy(hp0, hp, size); 655 656 /* Free previous tag, if any, and assign new one. */ 657 if (hip->in != NULL) 658 free(hip->in, M_NETGRAPH_TAG); 659 hip->in = hp; 660 661 /* 662 * Resolve hook names to pointers. 663 * 664 * As ng_findhook() is expensive operation to do it on every packet 665 * after tag matching check, we do it here and use resolved pointers 666 * where appropriate. 667 * 668 * XXX The drawback is that user can configure a hook to use 669 * ifMatch/ifNotMatch hooks that do not yet exist and will be added 670 * by user later, so that resolved pointers will be NULL even 671 * if the hook already exists, causing node to drop packets and 672 * user to report bugs. We could do check for this situation on 673 * every hook creation with pointers correction, but that involves 674 * re-resolving for all pointers in all hooks, up to O(n^2) operations, 675 * so we better document this in man page for user not to do 676 * configuration before creating all hooks. 677 */ 678 hip->hi_match = ng_findhook(NG_HOOK_NODE(hook), hip->in->ifMatch); 679 hip->hi_nonmatch = ng_findhook(NG_HOOK_NODE(hook), hip->in->ifNotMatch); 680 681 /* Fill internal values from API structures. */ 682 hip->in_tag_cookie = hip->in->tag_cookie; 683 hip->in_tag_id = hip->in->tag_id; 684 hip->in_tag_len = hip->in->tag_len; 685 hip->strip = hip->in->strip; 686 hip->in_tag_data = (void*)(hip->in->tag_data); 687 return (0); 688 } 689 690 /* 691 * Set the OUT tag values associated with a hook. 692 */ 693 static int 694 ng_tag_setdata_out(hook_p hook, const struct ng_tag_hookout *hp0) 695 { 696 const hinfo_p hip = NG_HOOK_PRIVATE(hook); 697 struct ng_tag_hookout *hp; 698 int size; 699 700 /* Make a copy of the tag values and data. */ 701 size = NG_TAG_HOOKOUT_SIZE(hp0->tag_len); 702 hp = malloc(size, M_NETGRAPH_TAG, M_WAITOK); 703 /* M_WAITOK can't return NULL. */ 704 bcopy(hp0, hp, size); 705 706 /* Free previous tag, if any, and assign new one. */ 707 if (hip->out != NULL) 708 free(hip->out, M_NETGRAPH_TAG); 709 hip->out = hp; 710 711 /* Fill internal values from API structures. */ 712 hip->out_tag_cookie = hip->out->tag_cookie; 713 hip->out_tag_id = hip->out->tag_id; 714 hip->out_tag_len = hip->out->tag_len; 715 hip->out_tag_data = (void*)(hip->out->tag_data); 716 return (0); 717 } 718